中文摘要：

采用Zn置换AgNO3溶液的方法制备具有不同形貌和结构的纳米Ag,研究AgNO3溶液的浓度对纳米Ag树枝生长速率、形貌和结构的影响。实验结果表明,纳米Ag树枝生长速率、形貌和结构主要取决于AgNO3溶液的浓度和反应时间。纳米Ag树枝生长速率主要取决于AgNO3溶液的浓度,浓度越高,生长速率越大。当AgNO3溶液的浓度为5mmol/L,反应初期的产物为Ag分形。随着时间延长,Ag分形转变为由纳米颗粒聚集而形成Ag枝晶,最后转变为单晶。当AgNO3溶液浓度在20～100mmol/L时,反应的产物均为Ag枝晶,但40mmol/L以下浓度溶液中生成的Ag枝晶由纳米晶粒组成,而60mmol/L以上浓度溶液中生成的Ag枝晶为单晶。通过控制AgNO3溶液的浓度和反应时间,可制备具有不同形貌和结构的纳米Ag。

英文摘要：

Nanostructured Ag with different morphologies and structures was prepared by replacement reaction（Zn versus AgNO3）.The influence of AgNO3 concentration on the growth speed,the morphology and the structure of the nanostructured Ag was investigated.Experimental results show that the growth speed,morphologies and structures of the nanostructured Ag strongly depend on AgNO3 concentration and reaction time.The growth speed is mainly dependent on the AgNO3 concentration;the higher the concentration,the faster the growth speed.When the AgNO3 concentration is 5 mmol/L,Ag fractal forms at the beginning stage,but the fractal transforms to dendrite consisting of nanoparticles and to monocrystal at last as the reaction proceeds.When the concentration is in the range of 20-100 mmol/L,the products are all Ag dendrites,but the dendrites consist of nanoparticles when the concentration is below 40 mmol/L while they are monocrystal when the concentration is above 60 mmol/L.Ag nanostructures with different morphologies and structures can be prepared by controlling AgNO3 concentration and reaction time.